Pixel device of a transflective-type liquid crystal panel

Abstract

A pixel device of a transflective-type LCD comprises an upper panel, a lower panel, a liquid crystal layer, and a liquid crystal film. The lower panel is assembled beneath the upper panel, and an upper surface of the lower panel is divided into a reflective region and a naked transmission region. The liquid crystal layer is interposed between the upper panel and the lower panel. The liquid crystal film is positioned above the liquid crystal layer to compensate possible retardation resulted from the liquid crystal layer.

1. A pixel device of a transfiective-type liquid crystal panel comprising:
 an upper panel; 
 a lower panel assembled beneath said upper panel; 
 a reflector formed on an upper surface of the lower panel to defined the upper surface having a reflective region and a transmission region; 
 a liquid crystal layer interposed between said upper panel and said lower panel; and 
 a liquid crystal film, which is set with an opposing spiral direction with respect to that of said liquid crystal layer, formed on said liquid crystal layer to compensate retardation of said liquid crystal layer; 
 wherein an ambient linear polarized light in the reflective region passing through the liquid crystal film and the liquid crystal layer being reflected by the reflector to result a first linear polarized light leaving the liquid crystal film with a polarizing direction substantially perpendicular to that of the ambient linear polarized light in the pixel device with a substantially non-operation voltage and a backlight linear polarized light in the transmission region passing through the liquid crystal layer and the liquid crystal film being transformed into a third linear polarized light leaving the liquid crystal film with a polarizing direction substantially perpendicular to that of the backlight linear polarized light in the pixel device with a substantially non-operation voltage. 
 
   
   
     2. The pixel device of  claim 1 , wherein a retardation difference between said liquid crystal film and said liquid crystal layer in said transmission region is less than about 30 nm. 
   
   
     3. The pixel device of  claim 1 , wherein a stacked structure comprises said liquid crystal layer in the reflective region and said liquid crystal film, acts as an optical modulation structure adapted to as a quarter-wave plate. 
   
   
     4. The pixel device of  claim 1 , wherein respective liquid crystal molecules in said liquid crystal film and said liquid crystal layer are perpendicular to each other. 
   
   
     5. The pixel device of  claim 1 , wherein respective liquid crystal molecules in said liquid crystal film and said liquid crystal layer make an angle of about 80 to about 100 degrees. 
   
   
     6. The pixel device of  claim 1  wherein a twist angle difference between said liquid crystal film and said liquid crystal layer is less than about 10 degrees. 
   
   
     7. The pixel device of  claim 1  further comprising a first polarizer on an upper surface of said upper panel and a second polarizer on a lower surface of said lower panel, and respective transmission axes of the first polarizer and the second polarizer are perpendicular to each other. 
   
   
     8. The pixel device of  claim 1 , wherein said liquid crystal film is a polymer film. 
   
   
     9. The pixel device of  claim 1 , wherein said liquid crystal layer is one of a twisted nematic type, a super twisted nematic type, and an hybrid nematic type, and said liquid crystal layer and said liquid crystal film belong to the same type. 
   
   
     10. The pixel device of  claim 1 , wherein the ambient linear polarized light in the reflective region passing through the liquid crystal film and the liquid crystal layer being reflected by the reflector to result a second polarized light leaving the liquid crystal film having a main polarizing direction substantially identical to that of the ambient linear polarized light in the pixel device with an operation voltage. 
   
   
     11. The pixel device of  claim 10  wherein the backlight linear polarized light in the transmission region passing through the liquid crystal layer and the liquid crystal film being transformed into a fourth polarized light having a main polarizing direction substantially perpendicular to that of the backlight linear polarized light in the pixel device with an operation voltage.